I have the next problem: My app has thousands of users. Every user has money that can be represented as the "money" field in the "User" entity. If a payable event occurs in the app then I have to make a payment between two users so I need to update "money" fields for two "User" entities in a transaction. But I can't do it in a transaction because each user is in a different entity group and on the other hand I cann't put two users in a single entity group, because thus the single entity group will have all users and datastore contention problem will arise.
I can't figure out how this use case can be implemented correctly or how to design a datastore model. Please, suggest best practices for this situation! -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
